Text to Brainfuck

'''
Text-to-Brainfuck Generator
This program reads a textfile from stdin and
writes Brainfuck to stdout
The output only uses one block in a Brainfuck,
which is the currently selected block. It leaves
the block with value 0.

Written in Python 3.5.2
'''




from math import sqrt
from sys import stdin, stdout


def refactor(nr):
    root = int(sqrt(nr))
    rest = nr - (root**2)
    return root, rest


def main():
    old = 0

    stdout.write('[-]')

    for character in stdin.read():
        _ord = ord(character)

        if old == _ord:
            stdout.write('.')
            continue

        deviation = _ord - old

        mult = refactor(abs(deviation))

        if 0 < deviation:
            if deviation < 6:
                stdout.write('{}.'.format('+'*deviation))
            else:
                stdout.write('>{}[<{}>-]<{}.'.format('+'*mult[0],'+'*mult[0],'+'*mult[1]))
        else:
            if deviation > -6:
                stdout.write('{}.'.format('-'*abs(deviation)))
            else:
                stdout.write('>{}[<{}>-]<{}.'.format('+'*mult[0],'-'*mult[0],'-'*mult[1]))


        old = _ord

    stdout.write('[-]')
    stdout.flush()


if __name__ == '__main__':
    main()